X-ray computed tomography (CT) has become a prominent tool for cardiac imaging since the introduction of multislice CT in 1998. This prominence has come progressively with the increase in the number of detector rows and in the scanner rotation speed. However, the accuracy of cardiac CT imaging is currently strongly dependent on the patient (patients with heartbeat arrythmia, who are more at risk, are more difficult to image), and this accuracy furthermore comes at the cost of a high dose. The long-term goal of this research is to enable highly accurate CT imaging of the whole heart independently of the patient condition and with a dose comparable to typical CT scans. We hypothesize this goal will be reached using a new scanning concept, called complete single-beat whole-heart (CSWH) scanning, where tomographically-complete data covering the full heart is obtained within one heartbeat. For this first research on cardiac imaging with CSWH scans, we will focus on the following aims: (1) development and implementation of reconstruction algorithms for accurate imaging from cone-beam data on relevant CSWH scans, (2) comparative evaluation of CSWH scans in terms of data requirement and dose imparted using various collimation strategies, (3) comparative evaluation of CSWH scans in terms of imaging performance using computer simulated data and real data of anthropomorphic phantoms and using human ROC observer studies.